|Pos.|Rider|Semi-Final Points|Final Points|Final Heats|Total Points|
|---|---|---|---|---|---|
|1|Jack Milne|13|15|(3,3,3,3,3)|28|
|2|Wilbur Lamoreaux|12|13|(3,3,3,1,3)|25|
|3|Cordy Milne|11|12|(2,3,2,3,2)|23|
|4|Jack Parker|11|10|(2,3,1,2,2)|21|
|5|Ginger Lees|10|9|(1,1,2,2,3)|19|
|6|Frank Charles|10|7|(0,0,1,3,3)|17|
|7|Lionel Van Praag|11|6|(3,0,-,3,0)|17|
|8|Bill Kitchen|7|9|(1,2,2,2,2)|16|
|9|George Newton|11|5|(3,0,0,0,2)|16|
|10|Eric Langton|12|4|(1,0,0,3,0)|16|
|11|Morian Hansen|7|8|(1,2,3,1,1)|15|
|12|Eric Chitty|11|4|(0,2,0,1,1)|15|
|13|Joe Abbott|8|6|(2,1,1,2,0)|14|
|14|Arthur Atkinson|8|6|(2,0,2,1,1)|14|
|15|Frank Varey|8|3|(0,1,1,0,1)|11|
|16|Tommy Croombs|6|2|(0,2,0,0,0)|8|
|17|Bob Harrison|7|-|-|7|
|18|Alec Statham|6|0|(0)|6|

Question: how many riders were not from the united states?
Answer: 15